1. Field of the Invention
The present invention relates to a printer, and particularly to a printer including a movable member which is biased by a spring with respect to a base member.
2. Description of the Background Art
A printer having a structure for restricting a delivery position of printing sheets of paper in a paper feed cassette has been known, and particularly a printer having such a structure has been known that a movable member bearing printing sheets in the paper feed cassette is lifted by springs from a bottom wall of the cassette for determining a position of the printing sheets in a direction of lifting the printing sheets from the bottom wall of the paper feed cassette (e.g., Japanese Utility Model Laying-Open No. 63-116439).
In Japanese Utility Model Laying-Open No. 63-116439, a cassette body is provided at its bottom wall with an engagement portion for engaging with an end of the spring, and is also provided at the bottom wall with an aperture for fitting to a convex portion formed on the spring. According to Japanese Utility Model Laying-Open No. 63-116439, an end of the spring is kept in engagement with the engagement portion of the bottom wall of the cassette body, and the convex portion of the spring kept in the above engaged state is inserted into the aperture at the bottom wall by utilizing an elastic force of the spring so that the spring can be fixed to the bottom wall.
According to the above structure, the aperture is formed at the cassette body for inserting the convex portion of the spring. This aperture connects the upper and lower surfaces of the bottom wall of the cassette body together. It may be desired to isolate the upper and lower surfaces of the bottom wall of the cassette body from each other by the bottom wall for example in such cases that the bottom wall form a part of a bottom wall of a casing of the printer and that it is desired to isolate inner and outer spaces of the cassette from each other for suppressing absorption of external moisture into the printing sheets inside the cassette. In these cases, it is necessary to close the aperture by another member. This increases the number of components of the printer, and consequently increases a manufacturing cost of the printer.
According to the above structure, the convex portion must be formed at the spring. For arranging the spring on the cassette body, the spring end must be engaged with the engagement portion of the cassette body, and the convex portion of the spring must be inserted into the aperture of the cassette body. Thus, relatively complicated processing and operations are required. These complicate manufacturing steps of the printer, and increase the number of the manufacturing steps of the printer. This also increases the manufacturing cost of the printer.